scope:

Main Body of Standard

The Standard for Safety UL 414, Meter Sockets (UL 414), has been utilized for certifications since the 1950s. The main body of UL 414 provides requirements for meter sockets associated with plug-in-type watthour and similar utility meters, test switches, metering transformer cabinets, and interiors. The standard limits the maximum ratings of the plug-in-type watthour and similar utility meters to 600 V AC and 400 A. The metering transformers cabinets and interiors are limited to a maximum rating of 600 V AC and 6000 A.

Supplement SA

The UL 414 Supplement SA provides additional construction, testing, and marking requirements utilized for accessories intended for use with meter sockets, such as meter socket extenders and meter socket adapters, or other similar equipment. This supplement has been updated over the past several years to accommodate requirements with assemblies containing connections for utility-interactive alternative energy sources. This supplement is used in conjunction with the main body requirements for the certification of meter socket adapters. The standard limits the maximum ratings of the meters socket extenders and adapters to 600 V AC and 400 A.

Proposed Supplement SB

A new Supplement SB has been submitted for inclusion into the UL 414 standard through the standard technical panel (STP) process. It builds upon the legacy Supplement SA requirements and provides additional guidance for construction and testing considerations for the systems and components associated with the connection of distributed generation equipment, which is currently not properly addressed in the Supplement SA. This supplement is limited in scope to meter socket extenders/adapters with connections for utility-interactive alternative energy sources, distributed generation equipment, and other similar equipment. As part of these updates, the requirements associated with distributed generation in the Supplement SA portion of the UL 414 standard will be removed once added to the Supplement SB.